<!DOCTYPE html>
<html>
  <head>
    <meta name="viewport" content="width=device-width, initial-scale=1">
    <script>
      window.addEventListener("message", function(event) {
        document.getElementById("paragraph").innerHTML = "Message received: " + event.data;
      });
      function sendMessage() {
        window.parent.postMessage("Hello from the WebView", "*");
      }
    </script>
  </head>
  <body>
    <h1>Web Messaging</h1>
    <p id="paragraph">No message received from Tabris.js</p>
    <button type="button" onclick="sendMessage()">Send Web Message</button>
  </body>
</html>
